Retrospective digital study of mandibular flexure in patients with long-span fixed restorations supported by natural teeth

PURPOSE: This retrospective study aims to evaluate the mandibular flexure on a long-span rigid fixed prosthesis supported by natural teeth. MATERIALS AND METHODS: Nine patients (five males and four females) were included in this study who had long-span rigid mandibular fixed prostheses for long-term (10–15 years) that have led to radiographic changes around the supporting teeth. The mandibular flexure was measured digitally after adhering reference markers to the prostheses. Intraoral scans were obtained at the minimum and maximum mouth openings before and after splitting the preexisting prostheses. The distances between the markers were measured, and mandibular flexure was calculated. RESULTS: This study showed a significant deviation (narrowing) of the mandible before and after splitting the rigid fixed prostheses (P value < 0.05). CONCLUSION: Digital analysis of the data collected from the patients in this retrospective study indicated that deviations occur during mandibular flexure. CLINICAL RELEVANCE: Splitting the full arch prosthesis could prevent the negative consequences of mandibular flexure on restorations. Trial registration The study was registered on clinicaltrials.gov with registration number NCT05617274 (15/11/2022)